diff options
Diffstat (limited to 'drivers/md/dm-thin.c')
| -rw-r--r-- | drivers/md/dm-thin.c | 284 |
1 files changed, 172 insertions, 112 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index ee29037ffc2e..726228b33a01 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -144,6 +144,7 @@ struct pool_features { bool zero_new_blocks:1; bool discard_enabled:1; bool discard_passdown:1; + bool error_if_no_space:1; }; struct thin_c; @@ -163,8 +164,7 @@ struct pool { int sectors_per_block_shift; struct pool_features pf; - unsigned low_water_triggered:1; /* A dm event has been sent */ - unsigned no_free_space:1; /* A -ENOSPC warning has been issued */ + bool low_water_triggered:1; /* A dm event has been sent */ struct dm_bio_prison *prison; struct dm_kcopyd_client *copier; @@ -198,7 +198,8 @@ struct pool { }; static enum pool_mode get_pool_mode(struct pool *pool); -static void set_pool_mode(struct pool *pool, enum pool_mode mode); +static void out_of_data_space(struct pool *pool); +static void metadata_operation_failed(struct pool *pool, const char *op, int r); /* * Target context for a pool. @@ -509,15 +510,16 @@ static void remap_and_issue(struct thin_c *tc, struct bio *bio, struct dm_thin_new_mapping { struct list_head list; - unsigned quiesced:1; - unsigned prepared:1; - unsigned pass_discard:1; + bool quiesced:1; + bool prepared:1; + bool pass_discard:1; + bool definitely_not_shared:1; + int err; struct thin_c *tc; dm_block_t virt_block; dm_block_t data_block; struct dm_bio_prison_cell *cell, *cell2; - int err; /* * If the bio covers the whole area of a block then we can avoid @@ -534,7 +536,7 @@ static void __maybe_add_mapping(struct dm_thin_new_mapping *m) struct pool *pool = m->tc->pool; if (m->quiesced && m->prepared) { - list_add(&m->list, &pool->prepared_mappings); + list_add_tail(&m->list, &pool->prepared_mappings); wake_worker(pool); } } @@ -548,7 +550,7 @@ static void copy_complete(int read_err, unsigned long write_err, void *context) m->err = read_err || write_err ? -EIO : 0; spin_lock_irqsave(&pool->lock, flags); - m->prepared = 1; + m->prepared = true; __maybe_add_mapping(m); spin_unlock_irqrestore(&pool->lock, flags); } @@ -563,7 +565,7 @@ static void overwrite_endio(struct bio *bio, int err) m->err = err; spin_lock_irqsave(&pool->lock, flags); - m->prepared = 1; + m->prepared = true; __maybe_add_mapping(m); spin_unlock_irqrestore(&pool->lock, flags); } @@ -640,9 +642,7 @@ static void process_prepared_mapping(struct dm_thin_new_mapping *m) */ r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block); if (r) { - DMERR_LIMIT("%s: dm_thin_insert_block() failed: error = %d", - dm_device_name(pool->pool_md), r); - set_pool_mode(pool, PM_READ_ONLY); + metadata_operation_failed(pool, "dm_thin_insert_block", r); cell_error(pool, m->cell); goto out; } @@ -683,7 +683,15 @@ static void process_prepared_discard_passdown(struct dm_thin_new_mapping *m) cell_defer_no_holder(tc, m->cell2); if (m->pass_discard) - remap_and_issue(tc, m->bio, m->data_block); + if (m->definitely_not_shared) + remap_and_issue(tc, m->bio, m->data_block); + else { + bool used = false; + if (dm_pool_block_is_used(tc->pool->pmd, m->data_block, &used) || used) + bio_endio(m->bio, 0); + else + remap_and_issue(tc, m->bio, m->data_block); + } else bio_endio(m->bio, 0); @@ -751,13 +759,17 @@ static int ensure_next_mapping(struct pool *pool) static struct dm_thin_new_mapping *get_next_mapping(struct pool *pool) { - struct dm_thin_new_mapping *r = pool->next_mapping; + struct dm_thin_new_mapping *m = pool->next_mapping; BUG_ON(!pool->next_mapping); + memset(m, 0, sizeof(struct dm_thin_new_mapping)); + INIT_LIST_HEAD(&m->list); + m->bio = NULL; + pool->next_mapping = NULL; - return r; + return m; } static void schedule_copy(struct thin_c *tc, dm_block_t virt_block, @@ -769,18 +781,13 @@ static void schedule_copy(struct thin_c *tc, dm_block_t virt_block, struct pool *pool = tc->pool; struct dm_thin_new_mapping *m = get_next_mapping(pool); - INIT_LIST_HEAD(&m->list); - m->quiesced = 0; - m->prepared = 0; m->tc = tc; m->virt_block = virt_block; m->data_block = data_dest; m->cell = cell; - m->err = 0; - m->bio = NULL; if (!dm_deferred_set_add_work(pool->shared_read_ds, &m->list)) - m->quiesced = 1; + m->quiesced = true; /* * IO to pool_dev remaps to the pool target's data_dev. @@ -840,15 +847,12 @@ static void schedule_zero(struct thin_c *tc, dm_block_t virt_block, struct pool *pool = tc->pool; struct dm_thin_new_mapping *m = get_next_mapping(pool); - INIT_LIST_HEAD(&m->list); - m->quiesced = 1; - m->prepared = 0; + m->quiesced = true; + m->prepared = false; m->tc = tc; m->virt_block = virt_block; m->data_block = data_block; m->cell = cell; - m->err = 0; - m->bio = NULL; /* * If the whole block of data is being overwritten or we are not @@ -895,41 +899,42 @@ static int commit(struct pool *pool) return -EINVAL; r = dm_pool_commit_metadata(pool->pmd); - if (r) { - DMERR_LIMIT("%s: dm_pool_commit_metadata failed: error = %d", - dm_device_name(pool->pool_md), r); - set_pool_mode(pool, PM_READ_ONLY); - } + if (r) + metadata_operation_failed(pool, "dm_pool_commit_metadata", r); return r; } -static int alloc_data_block(struct thin_c *tc, dm_block_t *result) +static void check_low_water_mark(struct pool *pool, dm_block_t free_blocks) { - int r; - dm_block_t free_blocks; unsigned long flags; - struct pool *pool = tc->pool; - - /* - * Once no_free_space is set we must not allow allocation to succeed. - * Otherwise it is difficult to explain, debug, test and support. - */ - if (pool->no_free_space) - return -ENOSPC; - - r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); - if (r) - return r; if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) { DMWARN("%s: reached low water mark for data device: sending event.", dm_device_name(pool->pool_md)); spin_lock_irqsave(&pool->lock, flags); - pool->low_water_triggered = 1; + pool->low_water_triggered = true; spin_unlock_irqrestore(&pool->lock, flags); dm_table_event(pool->ti->table); } +} + +static int alloc_data_block(struct thin_c *tc, dm_block_t *result) +{ + int r; + dm_block_t free_blocks; + struct pool *pool = tc->pool; + + if (get_pool_mode(pool) != PM_WRITE) + return -EINVAL; + + r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); + if (r) { + metadata_operation_failed(pool, "dm_pool_get_free_block_count", r); + return r; + } + + check_low_water_mark(pool, free_blocks); if (!free_blocks) { /* @@ -941,35 +946,20 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) return r; r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); - if (r) + if (r) { + metadata_operation_failed(pool, "dm_pool_get_free_block_count", r); return r; + } - /* - * If we still have no space we set a flag to avoid - * doing all this checking and return -ENOSPC. This - * flag serves as a latch that disallows allocations from - * this pool until the admin takes action (e.g. resize or - * table reload). - */ if (!free_blocks) { - DMWARN("%s: no free data space available.", - dm_device_name(pool->pool_md)); - spin_lock_irqsave(&pool->lock, flags); - pool->no_free_space = 1; - spin_unlock_irqrestore(&pool->lock, flags); + out_of_data_space(pool); return -ENOSPC; } } r = dm_pool_alloc_data_block(pool->pmd, result); if (r) { - if (r == -ENOSPC && - !dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) && - !free_blocks) { - DMWARN("%s: no free metadata space available.", - dm_device_name(pool->pool_md)); - set_pool_mode(pool, PM_READ_ONLY); - } + metadata_operation_failed(pool, "dm_pool_alloc_data_block", r); return r; } @@ -992,7 +982,21 @@ static void retry_on_resume(struct bio *bio) spin_unlock_irqrestore(&pool->lock, flags); } -static void no_space(struct pool *pool, struct dm_bio_prison_cell *cell) +static void handle_unserviceable_bio(struct pool *pool, struct bio *bio) +{ + /* + * When pool is read-only, no cell locking is needed because + * nothing is changing. + */ + WARN_ON_ONCE(get_pool_mode(pool) != PM_READ_ONLY); + + if (pool->pf.error_if_no_space) + bio_io_error(bio); + else + retry_on_resume(bio); +} + +static void retry_bios_on_resume(struct pool *pool, struct dm_bio_prison_cell *cell) { struct bio *bio; struct bio_list bios; @@ -1001,7 +1005,7 @@ static void no_space(struct pool *pool, struct dm_bio_prison_cell *cell) cell_release(pool, cell, &bios); while ((bio = bio_list_pop(&bios))) - retry_on_resume(bio); + handle_unserviceable_bio(pool, bio); } static void process_discard(struct thin_c *tc, struct bio *bio) @@ -1040,17 +1044,17 @@ static void process_discard(struct thin_c *tc, struct bio *bio) */ m = get_next_mapping(pool); m->tc = tc; - m->pass_discard = (!lookup_result.shared) && pool->pf.discard_passdown; + m->pass_discard = pool->pf.discard_passdown; + m->definitely_not_shared = !lookup_result.shared; m->virt_block = block; m->data_block = lookup_result.block; m->cell = cell; m->cell2 = cell2; - m->err = 0; m->bio = bio; if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list)) { spin_lock_irqsave(&pool->lock, flags); - list_add(&m->list, &pool->prepared_discards); + list_add_tail(&m->list, &pool->prepared_discards); spin_unlock_irqrestore(&pool->lock, flags); wake_worker(pool); } @@ -1105,13 +1109,12 @@ static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block, break; case -ENOSPC: - no_space(pool, cell); + retry_bios_on_resume(pool, cell); break; default: DMERR_LIMIT("%s: alloc_data_block() failed: error = %d", __func__, r); - set_pool_mode(pool, PM_READ_ONLY); cell_error(pool, cell); break; } @@ -1184,13 +1187,12 @@ static void provision_block(struct thin_c *tc, struct bio *bio, dm_block_t block break; case -ENOSPC: - no_space(pool, cell); + retry_bios_on_resume(pool, cell); break; default: DMERR_LIMIT("%s: alloc_data_block() failed: error = %d", __func__, r); - set_pool_mode(pool, PM_READ_ONLY); cell_error(pool, cell); break; } @@ -1257,7 +1259,7 @@ static void process_bio_read_only(struct thin_c *tc, struct bio *bio) switch (r) { case 0: if (lookup_result.shared && (rw == WRITE) && bio->bi_size) - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); else { inc_all_io_entry(tc->pool, bio); remap_and_issue(tc, bio, lookup_result.block); @@ -1266,7 +1268,7 @@ static void process_bio_read_only(struct thin_c *tc, struct bio *bio) case -ENODATA: if (rw != READ) { - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); break; } @@ -1390,16 +1392,16 @@ static enum pool_mode get_pool_mode(struct pool *pool) return pool->pf.mode; } -static void set_pool_mode(struct pool *pool, enum pool_mode mode) +static void set_pool_mode(struct pool *pool, enum pool_mode new_mode) { int r; + enum pool_mode old_mode = pool->pf.mode; - pool->pf.mode = mode; - - switch (mode) { + switch (new_mode) { case PM_FAIL: - DMERR("%s: switching pool to failure mode", - dm_device_name(pool->pool_md)); + if (old_mode != new_mode) + DMERR("%s: switching pool to failure mode", + dm_device_name(pool->pool_md)); dm_pool_metadata_read_only(pool->pmd); pool->process_bio = process_bio_fail; pool->process_discard = process_bio_fail; @@ -1408,13 +1410,15 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode) break; case PM_READ_ONLY: - DMERR("%s: switching pool to read-only mode", - dm_device_name(pool->pool_md)); + if (old_mode != new_mode) + DMERR("%s: switching pool to read-only mode", + dm_device_name(pool->pool_md)); r = dm_pool_abort_metadata(pool->pmd); if (r) { DMERR("%s: aborting transaction failed", dm_device_name(pool->pool_md)); - set_pool_mode(pool, PM_FAIL); + new_mode = PM_FAIL; + set_pool_mode(pool, new_mode); } else { dm_pool_metadata_read_only(pool->pmd); pool->process_bio = process_bio_read_only; @@ -1425,6 +1429,9 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode) break; case PM_WRITE: + if (old_mode != new_mode) + DMINFO("%s: switching pool to write mode", + dm_device_name(pool->pool_md)); dm_pool_metadata_read_write(pool->pmd); pool->process_bio = process_bio; pool->process_discard = process_discard; @@ -1432,6 +1439,35 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode) pool->process_prepared_discard = process_prepared_discard; break; } + + pool->pf.mode = new_mode; +} + +/* + * Rather than calling set_pool_mode directly, use these which describe the + * reason for mode degradation. + */ +static void out_of_data_space(struct pool *pool) +{ + DMERR_LIMIT("%s: no free data space available.", + dm_device_name(pool->pool_md)); + set_pool_mode(pool, PM_READ_ONLY); +} + +static void metadata_operation_failed(struct pool *pool, const char *op, int r) +{ + dm_block_t free_blocks; + + DMERR_LIMIT("%s: metadata operation '%s' failed: error = %d", + dm_device_name(pool->pool_md), op, r); + + if (r == -ENOSPC && + !dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) && + !free_blocks) + DMERR_LIMIT("%s: no free metadata space available.", + dm_device_name(pool->pool_md)); + + set_pool_mode(pool, PM_READ_ONLY); } /*----------------------------------------------------------------*/ @@ -1538,9 +1574,9 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio) if (get_pool_mode(tc->pool) == PM_READ_ONLY) { /* * This block isn't provisioned, and we have no way - * of doing so. Just error it. + * of doing so. */ - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); return DM_MAPIO_SUBMITTED; } /* fall through */ @@ -1648,6 +1684,17 @@ static int bind_control_target(struct pool *pool, struct dm_target *ti) enum pool_mode new_mode = pt->adjusted_pf.mode; /* + * Don't change the pool's mode until set_pool_mode() below. + * Otherwise the pool's process_* function pointers may + * not match the desired pool mode. + */ + pt->adjusted_pf.mode = old_mode; + + pool->ti = ti; + pool->pf = pt->adjusted_pf; + pool->low_water_blocks = pt->low_water_blocks; + + /* * If we were in PM_FAIL mode, rollback of metadata failed. We're * not going to recover without a thin_repair. So we never let the * pool move out of the old mode. On the other hand a PM_READ_ONLY @@ -1657,10 +1704,6 @@ static int bind_control_target(struct pool *pool, struct dm_target *ti) if (old_mode == PM_FAIL) new_mode = old_mode; - pool->ti = ti; - pool->low_water_blocks = pt->low_water_blocks; - pool->pf = pt->adjusted_pf; - set_pool_mode(pool, new_mode); return 0; @@ -1682,6 +1725,7 @@ static void pool_features_init(struct pool_features *pf) pf->zero_new_blocks = true; pf->discard_enabled = true; pf->discard_passdown = true; + pf->error_if_no_space = false; } static void __pool_destroy(struct pool *pool) @@ -1772,8 +1816,7 @@ static struct pool *pool_create(struct mapped_device *pool_md, bio_list_init(&pool->deferred_flush_bios); INIT_LIST_HEAD(&pool->prepared_mappings); INIT_LIST_HEAD(&pool->prepared_discards); - pool->low_water_triggered = 0; - pool->no_free_space = 0; + pool->low_water_triggered = false; bio_list_init(&pool->retry_on_resume_list); pool->shared_read_ds = dm_deferred_set_create(); @@ -1898,7 +1941,7 @@ static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf, const char *arg_name; static struct dm_arg _args[] = { - {0, 3, "Invalid number of pool feature arguments"}, + {0, 4, "Invalid number of pool feature arguments"}, }; /* @@ -1927,6 +1970,9 @@ static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf, else if (!strcasecmp(arg_name, "read_only")) pf->mode = PM_READ_ONLY; + else if (!strcasecmp(arg_name, "error_if_no_space")) + pf->error_if_no_space = true; + else { ti->error = "Unrecognised pool feature requested"; r = -EINVAL; @@ -1997,6 +2043,8 @@ static dm_block_t calc_metadata_threshold(struct pool_c *pt) * skip_block_zeroing: skips the zeroing of newly-provisioned blocks. * ignore_discard: disable discard * no_discard_passdown: don't pass discards down to the data device + * read_only: Don't allow any changes to be made to the pool metadata. + * error_if_no_space: error IOs, instead of queueing, if no space. */ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) { @@ -2192,11 +2240,13 @@ static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit) return -EINVAL; } else if (data_size > sb_data_size) { + if (sb_data_size) + DMINFO("%s: growing the data device from %llu to %llu blocks", + dm_device_name(pool->pool_md), + sb_data_size, (unsigned long long)data_size); r = dm_pool_resize_data_dev(pool->pmd, data_size); if (r) { - DMERR("%s: failed to resize data device", - dm_device_name(pool->pool_md)); - set_pool_mode(pool, PM_READ_ONLY); + metadata_operation_failed(pool, "dm_pool_resize_data_dev", r); return r; } @@ -2231,10 +2281,12 @@ static int maybe_resize_metadata_dev(struct dm_target *ti, bool *need_commit) return -EINVAL; } else if (metadata_dev_size > sb_metadata_dev_size) { + DMINFO("%s: growing the metadata device from %llu to %llu blocks", + dm_device_name(pool->pool_md), + sb_metadata_dev_size, metadata_dev_size); r = dm_pool_resize_metadata_dev(pool->pmd, metadata_dev_size); if (r) { - DMERR("%s: failed to resize metadata device", - dm_device_name(pool->pool_md)); + metadata_operation_failed(pool, "dm_pool_resize_metadata_dev", r); return r; } @@ -2290,8 +2342,7 @@ static void pool_resume(struct dm_target *ti) unsigned long flags; spin_lock_irqsave(&pool->lock, flags); - pool->low_water_triggered = 0; - pool->no_free_space = 0; + pool->low_water_triggered = false; __requeue_bios(pool); spin_unlock_irqrestore(&pool->lock, flags); @@ -2510,7 +2561,8 @@ static void emit_flags(struct pool_features *pf, char *result, unsigned sz, unsigned maxlen) { unsigned count = !pf->zero_new_blocks + !pf->discard_enabled + - !pf->discard_passdown + (pf->mode == PM_READ_ONLY); + !pf->discard_passdown + (pf->mode == PM_READ_ONLY) + + pf->error_if_no_space; DMEMIT("%u ", count); if (!pf->zero_new_blocks) @@ -2524,6 +2576,9 @@ static void emit_flags(struct pool_features *pf, char *result, if (pf->mode == PM_READ_ONLY) DMEMIT("read_only "); + + if (pf->error_if_no_space) + DMEMIT("error_if_no_space "); } /* @@ -2618,11 +2673,16 @@ static void pool_status(struct dm_target *ti, status_type_t type, DMEMIT("rw "); if (!pool->pf.discard_enabled) - DMEMIT("ignore_discard"); + DMEMIT("ignore_discard "); else if (pool->pf.discard_passdown) - DMEMIT("discard_passdown"); + DMEMIT("discard_passdown "); + else + DMEMIT("no_discard_passdown "); + + if (pool->pf.error_if_no_space) + DMEMIT("error_if_no_space "); else - DMEMIT("no_discard_passdown"); + DMEMIT("queue_if_no_space "); break; @@ -2721,7 +2781,7 @@ static struct target_type pool_target = { .name = "thin-pool", .features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE | DM_TARGET_IMMUTABLE, - .version = {1, 9, 0}, + .version = {1, 10, 0}, .module = THIS_MODULE, .ctr = pool_ctr, .dtr = pool_dtr, @@ -2899,7 +2959,7 @@ static int thin_endio(struct dm_target *ti, struct bio *bio, int err) spin_lock_irqsave(&pool->lock, flags); list_for_each_entry_safe(m, tmp, &work, list) { list_del(&m->list); - m->quiesced = 1; + m->quiesced = true; __maybe_add_mapping(m); } spin_unlock_irqrestore(&pool->lock, flags); @@ -2911,7 +2971,7 @@ static int thin_endio(struct dm_target *ti, struct bio *bio, int err) if (!list_empty(&work)) { spin_lock_irqsave(&pool->lock, flags); list_for_each_entry_safe(m, tmp, &work, list) - list_add(&m->list, &pool->prepared_discards); + list_add_tail(&m->list, &pool->prepared_discards); spin_unlock_irqrestore(&pool->lock, flags); wake_worker(pool); } @@ -3008,7 +3068,7 @@ static int thin_iterate_devices(struct dm_target *ti, static struct target_type thin_target = { .name = "thin", - .version = {1, 9, 0}, + .version = {1, 10, 0}, .module = THIS_MODULE, .ctr = thin_ctr, .dtr = thin_dtr, |